node-js file to pull webcam images

server.js

var config = require('./config.json')
var http = require(config.schema);
var fs = require('fs');

console.log("=========  startup =========")

var trafficCamHistory = []

// create required directories on startup
config.camImages.forEach(camera => {
    fs.mkdir(process.cwd() + "/cam-history/" + camera.id, { recursive: true }, (err) => {
        if (err.code !== 'EEXIST') throw err
        if (err.code === 'EEXIST') return
        console.log("created cam directory: " + process.cwd() + "/cam-history/" + camera.id)
    });
})


var camPullInterval = setInterval(function() {

    console.log("checking: " + new Date())

    config.camImages.forEach(camera => {
        var options = {method: 'HEAD', host: config.domain, port: 80, path: config.path + camera.id + config.extension};
        var req = http.request(options, function(res) {

            var eTag = res.headers['etag']

            var history = trafficCamHistory[camera.id] || []

            var found = history.find(eTagHistory => {
                return (eTagHistory == eTag)
            })
            
            if (!found) {
                var options = {method: 'GET', host: config.domain, port: 80, path: config.path + camera.id + config.extension};
                var getRequest = http.request(options, function(getResponse) {

                    var lastModified = getResponse.headers['last-modified']
                    var filename =  (new Date(lastModified).toISOString().replace(/T/, '_').replace(/\..+/, '').replace(/:/g, '-')) + ".jpeg"


                    var file = fs.createWriteStream(process.cwd() + "/cam-history/" + camera.id + "/" + filename);
                    getResponse.pipe(file);
                    console.log(camera.id + " saved: " + new Date())
                            
                })
                getRequest.end();

        
                history.push(eTag)
                trafficCamHistory[camera.id] = history
                console.log("new eTag found: " + camera.id + " date: " + new Date())
            }
            
        });
        req.end();
        
    });

}, 60000)


// uncomment to stop script after 1 hour ...
// setTimeout(function() {
//     clearInterval(camPullInterval)
// }, 60 * 60 * 1000)